Shark FAQs

by Dr. Jack Musick
|
August 3, 2010

Tiger shark, Galeocerdo cuvier

These occasional visitors to Virginia waters are usually found at least 10 miles offshore. They tend to come inshore at night and move into deeper waters during the day. They are opportunistic feeders on bony fishes, sharks, rays, sea turtles, sea snakes, sea birds, marine mammals, carrion, and garbage. Maximum length is 18 feet (females).

Photo courtesy Dennis Liberson.

Scalloped hammerhead, Sphyrna lewini

In the mid-Atlantic, these sharks migrate seasonally, over-wintering in warmer Gulf Stream waters south of Cape Hatteras. They arrive in Virginia coastal waters in June, and return south along the coast from August to October. They eat menhaden, mullet, flounder, and drums, crustaceans, stingrays, and small sharks. Maximum length is 14 ft.

Photo courtesy Dean Grubbs.

Sandbar shark, Carcharhinus plumbeus

These sharks are typically found over muddy or sandy bottoms to depths of more than 200 m (655 feet). They primarily eat small bottom fishes, mollusks, and crustaceans. The Chesapeake Bay is one of the most important sandbar shark nursery areas in the western Atlantic.

What are the most common shark species in Virginia waters?

The most common shark species found in Virginia waters are sandbar sharks, smooth dogfish, Atlantic sharpnose sharks, and dusky sharks. See slideshow above for additional details on each species. [top]

What is the conservation status of sharks?

Today, populations of large sharks are only a fraction of what they were in the 1970s, largely due to over-fishing. The population of sandbar sharks, Virginia's most common species, stands at about 50% of 1970s levels. This is an increase from the 15% levels seen during the late 1980s, before fisheries management plans started to have a positive effect. Current populations of sandtiger sharks (at 15% of 1970s levels), dusky sharks (25%), and tiger sharks (40%) remain severely depressed. Sharks are susceptible to over-fishing because they grow slowly, reach sexual maturity at an advanced age (most of the larger species reach sexually maturity at 6-21 years), and produce only 8-10 pups every other year. The lower Chesapeake Bay and the lagoons along the Eastern Shore constitute the principal nursery grounds for sandbar sharks. This is the most abundant large shark species on the Atlantic Coast, and the most important in both recreational and commercial fisheries. [top]

What is the focus of shark research at VIMS?

The Virginia Institute of Marine Science is one of four members of the National Shark Research Consortium. The VIMS Shark Research Program, established by Dr. Jack Musick, has been monitoring shark populations in the Chesapeake Bight using standardized, fishery-independent longline surveys since 1973. This long-term data set represents the longest running fishery-independent shark-monitoring program in the world. The scientists and students at VIMS provide detailed analyses of habitat use, age, growth, reproduction, trophic dynamics, and demographics of commercially, recreationally, and ecologically important shark species. [top]

Why are sharks important ecologically?

Sharks sit atop the food chain as apex predators. As such, they play an important ecological role in keeping prey populations healthy by removing weak, old, and infirm individuals. As shark populations decline due to over-fishing and habitat loss, prey populations can increase unchecked, leading to an overall decline in ecosystem health. [top]

How common are shark attacks?

Shark attacks are extremely rare. An individual is three times more likely to be hit by lightning than to be bitten by a shark. There were an average of 32 shark attacks per year in U.S. waters between 1990 and 2004. Of the 490 attacks during this 15-year span, 11 were fatal. Visit the International Shark Attack File for a comparison of the relative risk of shark attack versus other potential hazards. [top]

Where are shark attacks most common in the U.S.?

Most U.S. attacks occur in Florida. Incidents in Virginia are extremely rare and incidents in North Carolina are uncommon. There are only two unprovoked shark attacks on record in Virginia, a non-fatal incident in 1973 and a fatal attack in 2001. There have been 19 attacks in North Carolina between 1990 and 2004, 2 of them fatal. For a comprehensive database of shark-attack statistics, trends, and analyses, visit the International Shark Attack File. [top]

Are shark attacks becoming more common?

Long-term trends in the prevalence of shark-human interactions are directly correlated to human population and interest in marine recreation. Because more humans are spending more time in the ocean, the number of shark-human interactions and other marine-related injuries is generally increasing. Increased media coverage and scientific interest has also led to an increase in the number of shark-human interactions that are recorded. Sharp declines in shark populations during recent decades in many areas of the world as a result of over-fishing and habitat loss are reducing the potential for shark-human interactions. Local year-to-year variations in economic and social factors, weather, and ocean conditions significantly influence the abundance of sharks and humans in the water. As a result, short-term changes in the number of shark attacks—up or down—must be viewed with caution. Scientists prefer to view trends over longer periods of time (e.g., by decade) rather than trying to assign undue significance to year-to-year variability. (adapted from ISAF statment ) [top]

How can one minimize the already low risk of a shark attack?

Avoid being in the water when sharks are most likely to be present. Sharks generally feed around dawn and dusk and often move into shallow waters following prey such as menhaden and other small fish. When schools of bait fish are observed near the shoreline sharks and other predators may also be nearby. Along the coast of the U.S. sharks move north in the spring with warming temperatures, and south again in the fall as water temperatures cool. Visit the International Shark Attack File for more advice on reducing the risk of a shark encounter. [top]